1. Field of the Invention
The present invention relates to a label sticking method and a label sticking apparatus for sticking a label on a workpiece with great accuracy.
2. Description of the Related Art
In order to enjoy ease of photography when a camera is not carried, a lens-fitted film unit (its trade name is "Quick Snap Hi" and so forth) is provided by an assignee of the present application. As to the lens-fitted film unit, a unit body in which an unexposed photographic film and an exposure mechanism are beforehand built in is covered with a box-like case, for example, a paper case.
This box-like case has a complicated shape so that its material cost, its punching cost and so forth are expensive. Further, such a box-like case has shortcomings that an attachment process to the unit body is complex, and that it is troublesome to detach it at the time of recycling. In view of the foregoing, the assignee of the present application suggests an invention that an outer peripheral surface of the unit body is wrapped with a strip-like label instead of the box-like case. This invention is disclosed in U.S. patent application Ser. No. 08/683,758 filed on Jul. 17, 1996 (corresponding to Japanese Patent Laid-Open Publication No. 9-33996).
By the way, on a front face of the unit body, a protrusion for protecting a taking lens and a shutter mechanism is formed. On the other hand, an opening through which the protrusion projects is formed in the above-mentioned label. It is necessary to accurately adjust positions regarding the protrusion of the unit body and the opening of the label. However, there are variations in label punching positions of a label tape. Accordingly, when a label sticking operation is performed by using, for example, a robot hand provided with an absorption head, the position of the label absorbed on an absorption face of the absorption head is not fixed. Therefore, there arises a problem in that it is difficult to stick the label accurately. If the position of each label is accurately measured every absorption of the label and the robot hand is precisely controlled, it is possible to stick the label with great accuracy. However, in this case, there arises a problem in that it is difficult to perform the label sticking operation at high speed.